printf inside for loop



Hello Maxima ML:

I am trying to use printf() to format columns of floats. Using printf() 
inside block gave me no output, so I have reduced my query to using printf() 
inside a for loop with just integers:

1. for loop with print() looks ok:

(%i38) for n thru 3 do print(n);
1
2
3
(%o38)          done
=========================
2. for loop with printf() , here guided by the example in the Maxima manual.
no output.

(%i42) for n thru 3 do ev( printf(false,"~d",m),m=n );
(%o42)          done
 =========================
3. maybe I need to wrap n in ev()?  still no output

%i43) for n thru 3 do ev( printf(false,"~d",m),m=ev(n) );
(%o43)          done
======================
4. trying printf() in a simpler version: again no output.

%i40) for n thru 3 do printf(false,"~d",n);
(%o40)          done
==========================
5  perhaps I need to force some evaluation??  no output

(%i41) for n thru 3 do printf(false,"~d",ev(n));
(%o41)          done
==================
The manual suggest looking at Lisp references. Since
I have not studied Lisp, I thought someone here
could give me a quicker clue.

Any help would be most welcome.

Ted Woollett